$0 = 1
$1 = H * W
$21 = 0
$22 = 0
$23 = 0

while($0 <= $1)
  $2 = $0 - 1
  $3 = $2 / W
  $4 = $3 + 1
  $5 = $2 % W
  $6 = $5 + 1
  $7 = A[$4, $6]
  $8 = B[$4, $6]
  $12 = ($7 - $8) * ($7 - $8)
  $23 = $23 + $12
  $21 = $21 + $4 * $12
  $22 = $22 + $6 * $12
  $0 = $0 + 1
end

$21 = $21 / $23
$22 = $22 / $23
return ($21, $22)